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Stability of water yield in watersheds

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Science China Earth Sciences 2024年第2期67卷 483-496页

作者： Yu YAN Zhiyong LIU Xiaohong CHEN Liyan HUANG Center for water resources and Environment School of Civil EngineeringSun Yat-Sen UniversityGuangzhou510275China Southern Marine Science and engineering Guangdong Laboratory(Zhuhai) Zhuhai519082China

The hydrological system of a watershed is intricately influenced by both underlying characteristics and climate conditions.Understanding the variability in water yield is essential for effective water resources management and water security in the context of changing environments.In this study,we adopted the Budyko framework and leveraged simulations from the CMIP6 model to investigate the compensation effects of climate and underlying characteristics on watershed water yield.Based on Taylor expansion and Budyko framework,we estimated the sensitivity of watershed water yield to climate and underlying characteristics(the first-and second-order partial derivatives).By combining external watershed characteristics(e.g.,water yield ratios and underlying characteristics)with internal sensitivity coefficients,this study further used vine copula and principal component analysis to quantify the stability of watershed water yield.Our findings show:(1)water-yield changes related to underlying characteristics could be offset by climate-related water-yield changes across all climate zones,maintaining the water yield ratio steady(i.e.,the compensation effects).(2)However,global watersheds will turn more sensitive to underlying characteristics and less sensitive to climate variation in the future.Both climate-and underlying-related sensitivities increase in watersheds with arid climates.(3)The stability of watershed water yield will gradually diminish in the future.From 1901–1950to 2051–2100,the global stability of 280 watersheds drops from 0.054 to 0.021(i.e.,stability index identified by the joint probability).Particularly,the largest change in stability of water yield reaches-0.347±0.18 in arid regions.In semi-arid,semihumid,and humid regions,the changes are-0.039±0.010,-0.028±0.005,and-0.005±0.002,respectively.The findings provide a reference for the future sustainable water resources development under climate change,highlighting the vulnerability of the water resources in arid and semi-arid watersheds.

关键词： Hydrological system stability Compensation effects on water yield Sensitivities Budyko-Fu decomposition framework Global watersheds

Mechanical properties and fracture surface roughness of thermally damaged granite under dynamic splitting

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Deep Underground Science and engineering 2024年第1期3卷 103-116页

作者： Yijin Qian Peng Jia Songze Mao Jialiang Lu school of resources and civil engineering Northeastern UniversityShenyangChina

In order to understand the mechanical properties and the fracture surface roughness characteristics of thermally damaged granite under dynamic splitting,dynamic Brazilian splitting tests were conducted on granite samples after thermal treatment at 25,200,400,and 600℃.Results show that the dynamic peak splitting strength of thermally damaged granite samples increases with increasing strain rate,showing obvious strain‐rate sensitivity.With increasing temperature,thermally induced cracks in granite transform from intergranular cracks to intragranular cracks,and to a transgranular crack network.Thermally induced damages reduce the dynamic peak splitting strength and the maximum absorbed energy while increasing the peak radial strain.The fracture mode of the thermally damaged granite under dynamic loads is mode Ⅱ splitting failure.By using the axial roughness index Z2 a,the distribution ranges of the wedge‐shaped failure zones and the tensile failure zones in the fracture surfaces under dynamic Brazilian splitting can be effectively identified.The radial roughness index Z_(2)^(r)is sensitive to the strain rate and temperature.It shows a linear correlation with the peak splitting strength and the maximum absorbed energy and a linear negative correlation with the peak radial strain.Z_(2)^(r)can be used to quantitatively estimate the dynamic parameters based on the models proposed.

关键词： dynamic splitting fracture surface roughness granite strain rate thermal treatment

An Improved Golden Jackal Optimization Algorithm Based on Multi-strategy Mixing for Solving engineering Optimization Problems

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Journal of Bionic engineering 2024年第2期21卷 1092-1115页

作者： Jun Wang Wen-chuan Wang Kwok-wing Chau Lin Qiu Xiao-xue Hu Hong-fei Zang Dong-mei Xu College of water resources North China University of Water Resources and Electric PowerZhengzhou450046People’s Republic of China Department of civil and Environmental engineering The Hong Kong Polytechnic UniversityHong KongPeople’s Republic of China

Nowadays,optimization techniques are required in various engineering domains to find optimal solutions for complex problems.As a result,there is a growing tendency among scientists to enhance existing nature-inspired algorithms using various evolutionary strategies and to develop new nature-inspired optimization methods that can properly explore the feature space.The recently designed nature-inspired meta-heuristic,named the Golden Jackal Optimization(GJO),was inspired by the collaborative hunting actions of the golden jackal in nature to solve various challenging problems.However,like other approaches,the GJO has the limitations of poor exploitation ability,the ease of getting stuck in a local optimal region,and an improper balancing of exploration and exploitation.To overcome these limitations,this paper proposes an improved GJO algorithm based on multi-strategy mixing(LGJO).First,using a chaotic mapping strategy to initialize the population instead of using random parameters,this algorithm can generate initial solutions with good diversity in the search space.Second,a dynamic inertia weight based on cosine variation is proposed to make the search process more realistic and effectively balance the algorithm's global and local search capabilities.Finally,a position update strategy based on Gaussian mutation was introduced,fully utilizing the guidance role of the optimal individual to improve population diversity,effectively exploring unknown regions,and avoiding the algorithm falling into local optima.To evaluate the proposed algorithm,23 mathematical benchmark functions,CEC-2019 and CEC2021 tests are employed.The results are compared to high-quality,well-known optimization methods.The results of the proposed method are compared from different points of view,including the quality of the results,convergence behavior,and robustness.The superiority and high-quality performance of the proposed method are demonstrated by comparing the results.Furthermore,to demonstrate its applicability,it is employed to solve four c

关键词： Golden jackal optimization Chaotic mapping Dynamic inertia weight Dimensional Gaussian variation Muskingum

Research on Modeling and Parameter Identification of Comprehensive Load Model of Distribution Network in Industrial Park

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Chinese Journal of Electronics 2024年第1期33卷 264-273页

作者： Tingling WANG Xiaohe YAN school of Electric engineering North China University of Water Resources and Electric Power Wenzhou Polytechnic

With the rapid development of industrial parks, its load model research has become a hot spot. In order to study the load of power system in industrial park, based on the characteristics of the industrial park load, a comprehensive load admittance static model with full voltage range adaptability is considered, and a comprehensive load model of distribution network of the industrial park is established. A complete parameter identification of the model is carried out through chaos particle swarm optimization. The simulation results show that the model can effectively describe the load characteristics of the distribution network in industrial parks.

关键词： Industrial park Comprehensive load model Distribution network Chaos particle swarm optimization

Corrosion behaviors and kinetics of nanoscale zero-valent iron in water:A review

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Journal of Environmental Sciences 2024年第1期135卷 391-406页

作者： Chenliu Tang Xingyu Wang Yufei Zhang Nuo Liu Xiang Hu Research Group of water Pollution Control and water Reclamation College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Shanghai Collaborative Innovation Centre for WEEE Recycling School of Resources and Environmental EngineeringShanghai Polytechnic UniversityShanghai 201209China

Knowledge on corrosion behaviors and kinetics of nanoscale zero-valent iron(nZVI)in aquatic environment is particularly significant for understanding the reactivity,longevity and stability of nZVI,as well as providing theoretical guidance for developing a cost-effective nZVI-based technology and designing large-scale applications.Herein,this review gives a holistic overview on the corrosion behaviors and kinetics of nZVI in water.Firstly,Eh-pH diagram is introduced to predict the thermodynamics trend of iron corrosion.The morphological,structural,and compositional evolution of(modified-)nZVI under different environmental conditions,assisted with microscopic and spectroscopic evidence,is then summarized.Afterwards,common analytical methods and characterization technologies are categorized to establish time-resolved corrosion kinetics of nZVI in water.Specifically,stable models for calculating the corrosion rate constant of nZVI as well as electrochemical methods for monitoring the redox reaction are discussed,emphasizing their capabilities in studying the dynamic iron corrosion processes.Finally,in the future,more efforts are encouraged to study the corrosion behaviors of nZVI in long-term practical application and further build nanoparticles with precisely tailored properties.We expect that our work can deepen the understanding of the nZVI chemistry in aquatic environment.

关键词： Nanoscale zero-valent iron(nZVI) Corrosion behaviors Corrosion kinetics nZVI evolution

Gravel hardness effect on compaction characteristics of gravelly soil

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Journal of Mountain Science 2024年第4期21卷 1432-1443页

作者： SHI Yunfang LI Shengang JIANG Chen LIU Jinning school of resources and civil engineering Northeastern UniversityShenyang 110004China

The compaction characteristics of gravelly soil are affected by gravel hardness.To investigate the evolution and influencing mechanism of different gravel hardness on the compaction characteristics of gravelly soil,heavy compaction tests and crushing tests were conducted on gravelly soils with gravels originated from hard,soft and extremely soft rocks.According to orthogonal experiments and variance analysis,it was found that hardness has a significant impact on the maximum dry density of gravelly soil,followed by gravel content,and lastly,moisture content.For gravel compositions with an average saturated uniaxial compressive strength less than 60 MPa,the order of compacted maximum dry density is soft gravels>hard gravels>extremely soft gravels.Each type of gravelly soil has a threshold for gravel content,with 60%for hard and soft gravels and 50%for extremely soft gravels.Beyond these thresholds,the compacted dry density decreases significantly.There is a certain interaction between hardness,gravel content,and moisture content.Higher hardness increases the influence of gravel content,whereas lower hardness increases the influence of moisture content.Gravelly soils with the coarse aggregate(CA)between 0.7 and 0.8 typically achieve higher dry densities after compaction.In addition,the prediction equations for the particle breakage rate and CA ratio in the Bailey method were proposed to estimate the compaction performance of gravelly soil preliminarily.The results further revealed the compaction mechanism of different gravelly soils and can provide reference for subgrade filling construction.

关键词： Gravelly soil Hardness Compaction characteristics Crushing characteristics Particle breakage rate Bailey method

Precise regulation of the phase transformation for pyrolusite during the reduction roasting process

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 81-90页

作者： Ruofeng Wang Peng Gao Shuai Yuan Yanjun Li Yingzhi Liu Cheng Huang school of resources and civil engineering Northeastern UniversityShenyang 110819China National-Local Joint engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore resources Shenyang 110819China

The mechanism involved in the phase transformation process of pyrolusite (MnO_(2)) during roasting in a reducing atmosphere was systematically elucidated in this study,with the aim of effectively using low-grade complex manganese ore resources.According to single-factor experiment results,the roasted product with a divalent manganese (Mn^(2+)) distribution rate of 95.30% was obtained at a roasting time of 25 min,a roasting temperature of 700℃,a CO concentration of 20at%,and a total gas volume of 500 mL·min^(-1),in which the manganese was mainly in the form of manganosite (MnO).Scanning electron microscopy and Brunauer–Emmett–Teller theory demonstrated the microstructural evolution of the roasted product and the gradual reduction in the pyrolusite ore from the surface to the core Thermodynamic calculations,X-ray photoelectron spectroscopy,and X-ray diffractometry analyses determined that the phase transformation of pyrolusite followed the order of MnO_(2)→Mn_(2)O_(3)→Mn_(3)O_(4)→MnO phase by phase,and the reduction of manganese oxides in each valence state proceeded simultaneously.

关键词： pyrolusite phase transformation reduction roasting microstructural evolution reaction mechanism

Recent process developments in beneficiation and metallurgy of rare earths:A review

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Journal of Rare Earths 2024年第4期42卷 629-642页

作者： Shaokai Cheng Wenbo Li Yuexin Han Yongsheng Sun Peng Gao Xiaolong Zhang school of resources and civil engineering Northeastern UniversityShenyang110819China National-local Joint engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore resources Shenyang110819China

Rare earth elements(REEs)are irreplaceable materials supporting low-carbon technology and equip-ment,and their commercial demand and strategic position are becoming increasingly prominent.With the continuous depletion of rare earth(RE)resources,developing high-efficiency beneficiation and eco-friendly metallurgical processes has attracted widespread attention.This paper reviews the major minerals exploited for RE production and their deposits,as well as the beneficiation and metallurgical processes of RE minerals.Bastnaesite,monazite,mixed RE ores,and ion-adsorption clays are the main raw materials in the world to date.RE-bearing ores(except ion-adsorption minerals)are generally beneficiated by flotation,gravity and magnetic separation techniques.The mainstream metallurgical processes for bastnaesite,monazite and mixed RE concentrates are oxidation roasting-HCl leaching,caustic soda decomposition and high-temperature concentrated sulfuric acid roasting,respectively.Ion-adsorption clays are directly processed by in situ leaching-precipitation/solvent extraction.To achieve the sustainable development of RE resources,it is essential to further explore innovative techniques to achievecomprehensive utilization and cleaner production.

关键词： Rare earths Beneficiation processes Metallurgical processes Cleaner production

Stress relaxation properties of calcium silicate hydrate:a molecular dynamics study

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2024年第2期25卷 97-115页

作者： Zhicheng GENG Shengwen TANG Yang WANG Hubao A Zhen HE Kai WU Lei WANG State Key Laboratory of water resources engineering and Management Wuhan UniversityWuhan430072China Key Laboratory of Advanced civil engineering Materials of Ministry of Education School of Materials Science and EngineeringTongji UniversityShanghai200092China College of Materials Science and engineering Xi’an University of Architecture and TechnologyXi’an710055China

The time-dependent viscoelastic response of cement-based materials to applied deformation is far from fully understood at the atomic level.Calcium silicate hydrate(C-S-H),the main hydration product of Portland cement,is responsible for the viscoelastic mechanism of cement-based materials.In this study,a molecular model of C-S-H was developed to explain the stress relaxation characteristics of C-S-H at different initial deformation states,Ca/Si ratios,temperatures,and water contents,which cannot be accessed experimentally.The stress relaxation of C-S-H occurs regardless of whether it is subjected to initial shear,tensile,or compressive deformation,and shows a heterogeneous characteristic.water plays a crucial role in the stress relaxation process.A large Ca/Si ratio and high temperature reduce the cohesion between the calcium-silicate layer and the interlayer region,and the viscosity of the interlayer region,thereby accelerating the stress relaxation of C-S-H.The effect of the hydrogen bond network and the morphology of C-S-H on the evolution of the stress relaxation characteristics of C-S-H at different water contents was elucidated by nonaffine mean squared displacement.Our results shed light on the stress relaxation characteristics of C-S-H from a microscopic perspective,bridging the gap between the microscopic phenomena and the underlying atomic-level mechanisms.

关键词： Calcium silicate hydrate(C-S-H) Stress relaxation Ca/Si ratio Temperature water content Atomic simulation